The boxed warning on the labels of all tumor necrosis factor alpha (TNF-alpha) inhibitors will be updated to warn about the risk for serious and sometimes fatal infection from 2 bacterial pathogens, Legionella and Listeria, the US Food and Drug Administration (FDA) announced today. TNF-alpha blockers are used to treat rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, plaque psoriasis, and juvenile idiopathic arthritis, as well as Crohn's disease and ulcerative colitis. Because they suppress the immune system, these drugs come with a known risk for serious, life-threatening, opportunistic infections, which is a risk previously highlighted in the boxed warning on their labels.